JPH04220623A - Liquid crystal display unit - Google Patents

Abstract

PURPOSE:To prevent a connected part of tape automated bonding from being peeled and an input terminal and wire bonding from being cut by providing a reinforcing member for connecting and fixing a liquid crystal display panel to a printed circuit board. CONSTITUTION:Printed circuit boards (PCB) 2 for driving an liquid crystal display (LCD) 1 are disposed on the three sides of the liquid crystal panel (LCD) 1 and the terminal of the LCD 1 is electrically connected to the terminal of the PCB 2 via tape automated bonding (TAB) 3 to which a driving integrated circuit is mounted. A long plate-shaped reinforcing member 4 is fixed to the end (terminal) portion of the LCD 1 and to the reverse face of the end portion of the PCB 2 using a pressure sensitive adhesive double coated tape. The reinforcing member 4 is made of e.g. polyester tapes laminated and stuck together or a hard material such as an acrylic plate.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention uses a TAB method for electrically connecting a liquid crystal display panel (hereinafter referred to as LCD) and a printed wiring board (hereinafter referred to as PCB) using TAB (tape automated bonding). The present invention relates to a liquid crystal display device.

0002

[Prior Art] A liquid crystal display device consists of a shield case and two transparent glass substrates each having a transparent pixel electrode provided on each opposing surface, stacked one on top of the other at a predetermined distance, and liquid crystal sealed between the two substrates. It is composed of an LCD, a PCB for driving the LCD, and a TAB on which an IC for driving the LCD is mounted and electrically connects the LCD and the PCB.

Conventional devices with such a structure include:
For example, Japanese Patent Application Laid-Open No. 1-136122 can be cited.

0004

[Problems to be Solved by the Invention] In such a liquid crystal display device, mechanical stress is applied to the TAB due to stress applied to the PCB during the assembly process, and the connection between the output terminal portion of the TAB connected to the input terminal of the LCD is affected. There were problems such as parts peeling off, TAB input terminals breaking, cracks appearing in the resin covering the drive IC chip mounted on the TAB, and wire bonding breaking.

An object of the present invention is to provide a liquid crystal display device that can prevent mechanical stress from being applied to the TAB and prevent the TAB from coming off, input terminals breaking, and wire bonding breaking.

[0006]

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a liquid crystal display device having an LCD, a PCB, and a TAB electrically connecting the LCD and the PCB. The present invention is characterized in that a reinforcing member is provided to connect and fix the LCD and the PCB.

[0007]

[Function] In the liquid crystal display device of the present invention, since the LCD and PCB are connected and fixed by a reinforcing material, the mechanical stress applied to the TAB can be reduced, so that it is possible to prevent the TAB from peeling off or the input terminal from breaking.

[0008]

[Example] Example 1 FIG. 1 shows the back side (
FIG. 3 is a schematic plan view of the LCD, PCB, and TAB viewed from the side opposite to the display screen.

1 is LCD, 2 is PCB, 3 is TAB, 4
is a reinforcement. In other words, there are LCs around three sides of LCD1.
A PCB 2 for driving D1 is arranged, and terminals of the LCD 1 and terminals of the PCB 2 are electrically connected via a plurality of TABs 3 on which driving ICs (not shown) are mounted. The TABs 3 are provided around three sides of the LCD 1, but in FIG. 1, the TABs around two sides are hidden by the reinforcing material 4 and cannot be seen. In this embodiment, two long plate-shaped reinforcing members 4 as shown in the figure are fixed to the back side of the end (terminal part) of the LCD 1 and the end of the PCB 2 using double-sided adhesive tape. The reinforcing material 4 is made of a hard material such as, for example, a polyester tape having a thickness of 0.1 mm that is laminated and bonded to have a thickness of 0.7 mm, or an acrylic plate.

[0010] There are limits to how the assembly process of a liquid crystal display device can be performed without applying stress to the PCB. In this embodiment, as mentioned above, since the LCD1 and PCB2 are firmly fixed by the reinforcing material 4 and the double-sided adhesive tape, the LCD1 and PCB2 have little mechanical deformation, and the TAB
Since direct mechanical stress is not easily applied to 3 itself, L
The connection part of TAB3 connected to the input terminal of CD1 may peel off, the input terminal of TAB3 may break, the resin covering the drive IC chip (not shown) mounted on TAB3 may crack, and the wire bonding may break. can be prevented. In addition, if the TAB peels off or the input terminal breaks, you may have to throw away the expensive TAB or
It used to take a lot of time to recover defective ABs and drive ICs, but these losses can be prevented.

Embodiment 2 FIG. 2 is a schematic plan view of the LCD, PCB, and TAB of a liquid crystal display device according to a second embodiment of the present invention, viewed from the display screen side.

[0012] If the TAB connection is peeled off or the input terminal is broken, the L
It was found that this phenomenon occurs most often at the four corners of the CD, so in this example, in order to improve the mechanical strength of this area, reinforcing materials 4 made of the same hard material as in Example 1 were attached to the four corners with double-sided adhesive. It was fixed with tape. In this example, Example 1
Needless to say, it has a similar effect.

Embodiment 3 FIG. 3 is a schematic plan view of the LCD, PCB, and TAB of a liquid crystal display device according to a third embodiment of the present invention, viewed from the display screen side.

In this embodiment, unlike the first and second embodiments described above, the reinforcing member 4 is not provided as a separate member, but the shape of the PCB 2 is changed to the shape shown in the figure, and the reinforcing portion 40 is integrated into the PCB 2. The reinforcing portion 40 of this PCB 2 was directly fixed to the LCD 1 using double-sided adhesive tape. In this embodiment as well, the first,
Needless to say, this embodiment has the same effects as the second embodiment. In addition, in this example, no special reinforcing material is required,
Moreover, the reinforcing material installation process can be simplified.

Although the present invention has been specifically explained based on the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various changes can be made without departing from the gist of the invention. be. For example, in the above example,
Although double-sided adhesive tape was used to fix the LCD 1, PCB 2 and the reinforcing material 4 or the reinforcing part 40, they may be fixed using an adhesive, an epoxy resin, or the like.

[0016]

[Effects of the Invention] As explained above, in the present invention, the LCD
This can be reinforced by connecting and fixing the and PCB with a reinforcing material, so no direct mechanical stress is applied to the TAB, and the TA
This prevents B from peeling off and input terminals breaking. As a result, T
It is possible to reduce the amount of AB used and the playback time.

[Brief explanation of the drawing]

FIG. 1: The back side of a liquid crystal display device according to a first embodiment of the invention (
FIG. 3 is a schematic plan view of the LCD, PCB, and TAB viewed from the side opposite to the display screen.

FIG. 2 is a schematic plan view of an LCD, a PCB, and a TAB as seen from the display screen side of a liquid crystal display device according to a second embodiment of the present invention.

FIG. 3 is a schematic plan view of an LCD, a PCB, and a TAB as seen from the display screen side of a liquid crystal display device according to a third embodiment of the present invention.

[Explanation of symbols]

1 LCD 2 PCB 3 TAB 4 Reinforcement material 40 Reinforcement part

Claims (1)

[Claims] Claim 1: A liquid crystal display panel, a printed wiring board,
A liquid crystal display device having a TAB for electrically connecting the liquid crystal display panel and the printed wiring board, characterized in that a reinforcing member is provided for connecting and fixing the liquid crystal display panel and the printed wiring board. Display device.